Exactly - well said. As you already know (these are really 'Notes' to clarify my own understanding - as I know you know) - real combat is fluid and requires an instantaneous adaptation. My view is that this ability stems from years of experience endlessly repeating the same movement - or patterns of movements (in a disciplined manner) - whilst participating in sparring (or various other types of fighting) - where all this ingrained activity comes out (due to necessity) and manifests in all kinds of weird and wonderful ways!
Usually, simplicity prevails over the complex in such situations defined through 'immediacy' - and much of the modern 'Bunkai' is so very intricate and diverse that I doubt any of it could be realistically applied in the few seconds required to nullify an attack AND take away an opponent's ability to effectively respond. (Whilst holding one of their arms - the opponent still has a head, one arm and two legs free to respond - more than enough to be effective).
When I think back to training with yourself in Hereford and Cardiff (and the Tensho Kata you demonstrated in Sutton) - I remember your weight being firmly 'dropped' (rooted) whilst you also seem to 'float' - like a cork bobbing about on the surface of the water! This manifestation is continuous and effortless whilst being retained whether you are standing still, moving (in any direction) or even sitting down.
From this foundation your arms and legs are 'moved' depending upon the Kata, Basic or exercise being demonstrated. I suppose what you are saying is that modern Bunkai focuses too much upon the movement of the arms and legs - but tends to by-pass (or 'ignore') the need to be 'rooted' and to 'move' properly from this root.